Day 8: Extremophiles enrichment or JP shows off his skills (26.2.2013)

JP plated bacteria from some of the Antarctic samples we took last week. LB and a minimal medium R2A were used with or without cadmium cations or tellurite anion on agar plates. Some plates were incubated at 4°, 25°, and 50°C. This process should select for aerobic bacteria that are resistant to either cadmium or tellurium and might be good candidates to make CdTe nanoparticles. Also, Te-resistant bacteria might be able to reduce and methylate tellurium salts.

Below on the left is a photograph of an R2A plate, deftly divided into octrants for inocula from 8 samples taken at Dee Island and near Arturo Pratt Base amended with 200 µg/mL of CdCl2.

On the right is a photograph of an LB/agar plate with an inoculum from the hot spring at Kroner Lake on Deception Island, Antarctica. The temperature where the samples was taken was a "JP-certified" 52.6°C. Grown in a metal-free LB medium and incubated at 50 degrees overnight, the red arrow indicates a colony of a possible Antarctic thermophile (JP has some pretty strange things on his fingers). The next step will be to streak bacteria from that colony onto a fresh LB/agar plate to make sure it's a monoculture and then to grow liquid monocultures if that's successful.

Petri dish used to select for cadmium-resistant microbes

Selecting for thermophiles on a complex growth medium

The rules of the zodiac were explicitly expressed in the INACH training sessions in Punta Arenas before we arrived in Antarctica: everyone helps everyone else getting in and out of the zodiac. Everyone helps with everyone else's research equipment (see Day 15). Wet feet are dangerous and so far I only saw this problem a few times in a few hundred "people-zodiac-tranfer" events. Jota told us before we left for Antarctica this year that he had a wet feet accident last year on his Antarctic adventure and it was very bad. The zodiacs are powered by one or two outboard motors. When sampling off the Aquiles (see above) they were always two outboards.

About food on Aquiles: a light breakfast--light for Americans (coffee or tea, juice, bread, butter, or cheese only)--before sampling trips. After we returned from a full morning out and back in the zodiacs, lunch was at ~1 pm and then we ate quite well (soup, meat, starch, a few vegetables, bread, and desert) before often going sampling again. Dinner was 7+ pm, again meat, carbohydrates, a bread, a few vegetables, and desert.